The incremental effect of positron emission tomography on diagnostic accuracy in the initial staging of esophageal carcinoma

Association between prognosis and lymph node status using 18F-fluorodeoxyglucose-positron emission tomography in esophageal squamous cell carcinoma treated with esophagectomy post-neoadjuvant chemotherapy

BACKGROUND

There are few reports on the associations between lymph node (LN) status, determined by preoperative 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET), and prognosis in patients with locally advanced esophageal squamous cell carcinoma (ESCC) who underwent esophagectomy post-neoadjuvant chemotherapy (NCT). Additionally, details on the diagnostic performance of LN metastasis determination based on pathological examination versus FDG-PET have not been reported. In this study, we aimed to evaluate the associations among LN status using FDG-PET, LN status based on pathological examination, and prognosis in patients with locally advanced ESCC who underwent esophagectomy post-NCT.

METHODS

We reviewed the data of 124 consecutive patients with ESCC who underwent esophagectomy with R0 resection post-NCT between December 2008 and August 2022 and were evaluated pre- and post-NCT using FDG-PET. The associations among LN status using FDG-PET, LN status based on pathological examination, and prognosis were assessed.

RESULTS

Station-by-station analysis of PET-positive LNs pre- and post-NCT correlated significantly with pathological LN metastases (sensitivity, specificity, and accuracy pre- and post-NCT: 51.6%, 96.0%, and 92.1%; and 28.2%, 99.5%, and 93.1%, respectively; both p < 0.0001). Using univariate and multivariate analyses, LN status determined using PET post-NCT was a significant independent predictor of both recurrence-free survival and overall survival.

CONCLUSION

The LN status assessed using FDG-PET post-NCT was significantly associated with the pathological LN status and prognosis in patients with ESCC who underwent esophagectomy post-NCT. Therefore, FDG-PET is a useful diagnostic tool for preoperatively predicting pathological LN metastasis and survival in these patients and could provide valuable information for selecting individualized treatment strategies.

Nomogram for predicting the likelihood of liver metastases at initial diagnosis in patients with Siewert type II gastroesophageal junction adenocarcinoma

The liver is one of the most ordinary metastatic sites of gastroesophageal junction adenocarcinoma and significantly affects its prognosis. Therefore, this study tried to construct a nomogram that can be applied to predict the likelihood of liver metastases from gastroesophageal junction adenocarcinoma. 3001 eligible patients diagnosed with gastroesophageal junction adenocarcinoma between 2010 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database were involved in the analysis. Patients were randomly divided into a training cohort and an internal validation cohort using R software, with an allocation ratio of 7:3. According to the consequences of univariate and multivariate logistic regression, we constructed a nomogram for predicting the risk of liver metastases. The discrimination and calibration ability of the nomogram was appraised by the C-index, ROC curve, calibration plots, and decision curve analysis (DCA). We also used Kaplan-Meier survival curves to compare differences in overall survival in patients with gastroesophageal junction adenocarcinoma with and without liver metastases. Liver metastases developed in 281 of 3001 eligible patients. The overall survival of patients with gastroesophageal junction adenocarcinoma with liver metastases before and after propensity score matching (PSM) was obviously lower than that of patients without liver metastases. Six risk factors were finally recognized by multivariate logistic regression, and a nomogram was constructed. The C-index was 0.816 in the training cohort and 0.771 in the validation cohort, demonstrating the good predictive capacity of the nomogram. The ROC curve, calibration curve, and decision curve analysis further demonstrated the good performance of the predictive model. The nomogram can accurately predict the likelihood of liver metastases in gastroesophageal junction adenocarcinoma patients.

Outcomes of solitary postoperative recurrence of esophageal squamous cell carcinoma diagnosed with FDG-PET/CT and treated with definitive radiation therapy

BACKGROUND

Surgical resection of esophageal cancer is frequently performed to achieve a complete cure. However, the postoperative recurrence rate is 36.8-42.5%, leading to poor prognosis. Radiation therapy has been used to treat recurrences; solitary recurrence has been proposed as a prognostic factor for radiation therapy, though its significance is unclear. ¹⁸F-fluorodeoxyglucose positron emission tomography is a highly accurate diagnostic modality for esophageal cancer. This retrospective study aimed to analyze the outcomes of solitary postoperative recurrences of esophageal squamous cell carcinoma diagnosed with ¹⁸F-fluorodeoxyglucose positron emission tomography and treated with definitive radiation therapy.

METHODS

We examined 27 patients who underwent definitive radiation therapy for single or multiple postoperative recurrences of esophageal squamous cell carcinoma between May 2015 and April 2021. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography was performed within 3 months before the commencement of radiation therapy. Kaplan-Meier, univariate, and multivariate analyses were performed to examine the overall survival and identify potential prognostic factors.

RESULTS

The 1-, 2-, and 3-year overall survival rates were 85.2%, 62.6%, and 47.3%, respectively, and solitary recurrence was the only significant factor associated with overall survival (P = 0.003). The 1-, 2-, and 3-year overall survival rates in patients with solitary recurrence were 91.7%, 80.2%, and 80.2%, respectively, and in patients with multiple recurrences they were 80.0%, 50.3%, and 25.1%, respectively. Multivariate analysis also showed solitary recurrence as a significant factor for overall survival.

CONCLUSIONS

When diagnosed with ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography, solitary recurrence appears to have a more favorable prognosis than multiple recurrences.

18F-Fluorodeoxyglucose Positron Emission Tomography Parameters can Predict Long-Term Outcome Following Trimodality Treatment for Oesophageal Cancer

AIMS

¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸FDG-PET/CT) is routinely used for the pre-treatment staging of oesophageal or gastro-oesophageal junction cancers (EGEJC). The aim of this study was to identify objective ¹⁸FDG-PET/CT-derived parameters that can aid in predicting the patterns of recurrence and prognostication in patients with EGEJC.

PATIENTS AND METHODS

EGEJC patients referred for consideration of preoperative chemoradiation therapy were identified and clinicopathological data were collected. ¹⁸FDG-PET/CT imaging data were reviewed and correlated with treatment outcomes. Maximum standardised uptake value (SUV_max), metabolic tumour volume (MTV) and total lesion glycolysis were assessed and association with recurrence-free survival (RFS), locoregional recurrence-free survival (LR-RFS), oesophageal cancer-specific survival (ECSS) and overall survival were evaluated using receiver operating characteristic curves, as well as Cox regression and Kaplan-Meier models.

RESULTS

In total, 191 EGEJC patients completed trimodality treatment and 164 with ¹⁸FDG-PET/CT data were included in this analysis. At the time of analysis, 15 (9.1%), 70 (42.7%) and two (1.2%) patients were noted to have locoregional, distant and both locoregional and distant metastases, respectively. The median RFS was 30 months (9.6-50.4) and the 5-year RFS was 31.1%. The 5-year overall survival and ECSS were both noted to be 34.8%. Pre-treatment MTV₂₅ > 28.5 cm³ (P = 0.029), MTV₄₀ > 12.4 cm³ (P = 0.018) and MTV₅₀ > 10.2 cm³ (P = 0.005) predicted for worse LR-RFS, ECSS and overall survival for MTV definition of voxels ≥25%, 40% and 50% of SUV_max.

CONCLUSION

¹⁸FDG-PET/CT parameters MTV and total lesion glycolysis are useful prognostic tools to predict for LR-RFS, ECSS and overall survival in EGEJC. MTV had the highest accuracy in predicting clinical outcomes. The volume cut-off points we identified for different MTV thresholds predicted outcomes with significant accuracy and may potentially be used for decision making in clinical practice.

Blood biomarkers as predictors of pathological lymph node metastasis in clinical stage T1N0 esophageal squamous cell carcinoma

Accurate preoperative evaluation of lymph node (LN) metastasis is important for determining the treatment strategy for superficial esophageal cancer. Blood biomarkers, such as the neutrophil-lymphocyte, platelet-lymphocyte, and lymphocyte-monocyte ratios (NLR, PLR, and LMR, respectively), have clinical applications as predictors of LN metastasis for different cancers. Here, we investigated the use of these ratios as predictors of pathological LN metastasis and prognosis in patients with clinical stage T1N0M0 esophageal squamous cell carcinoma (ESCC). Patients (n = 185) with cT1N0M0 ESCC who underwent esophagectomy with R0 resection between April 2003 and August 2021 were enrolled. We investigated the ability of pretreatment NLR, PLR, and LMR to predict pathological LN metastasis. The optimal cutoff values of NLR, PLR, and LMR to predict pathological LN metastasis were 2.1, 122, and 4.8, respectively. Univariate and multivariate analyses revealed that the primary tumor length, depth of invasion, and NLR were significant predictors of LN metastasis. Furthermore, similar to the 5-year overall survival, the 5-year relapse-free survival was significantly better in the low NLR group than in the high NLR group. The NLR was the most useful predictor of pathological LN metastasis. Patients diagnosed with clinical stage I ESCC and with a high NLR require adequate LN dissection and may be good candidates for preoperative adjuvant therapy.

Prognostic Assessment of Interim F18-Fluorodeoxyglucose Positron Emission Tomography in Esophageal Cancer Treated With Chemoradiation With or Without Surgery

Purpose

This study aimed to evaluate if the F18-fluorodeoxyglucose positron emission tomography (F18-FDG PET) response after two weeks of chemoradiation for locoregionally advanced esophageal cancer (staged Tumor (T) 3 and/or Nodes (N)+ Metastases (M) 0) was linked to the pathologic response for patients undergoing surgery, to disease-free survival (DFS) or overall survival (OS).

Materials and Methods

Between March 2006 and September 2017, 40 patients were prospectively enrolled in our study, gave written consent, and had PET scans performed before treatment and after two weeks of chemoradiation. One patient did not undergo his two-week PET without informing study coordinators and was excluded from analyses.

Results

The median age at diagnosis was 62 years. Seventy-two percent of patients had N+ disease. Median OS for the entire group was 24 months. Five-year overall survival was 17%. Survival curves for patients with no PET response, minor PET response, or good PET response overlapped and were not statistically different. For the 25 patients who underwent surgery, the positive predictive value (PPV) of the PET response relative to the pathologic response was 75% and the negative predictive value (NPV) was 62%. In study patients, the crude recurrence rate was 68% and there was no correlation between PET response and DFS.

Conclusion

In our study, interim PET response after two weeks of chemoradiation for locoregionally advanced esophageal cancer was not predictive of outcome or pathologic response. Based on our data and current literature, interim PET should not be used to alter treatment (whether to escalate neo-adjuvant treatment or omit surgery).

Measuring distance from the incisors to the esophageal cancer by FDG PET/CT: endoscopy as the reference

Background

Using endoscopy as the reference, this study evaluated the accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in measuring distance from the incisors to the PET detectable esophageal cancer. If there is high concordance between endoscopic and PET measurements, our results may provide a basis to use FDG PET/CT in cooperation with endoscopic measurement to localize those PET/CT and CT undetectable esophageal tumors for radiotherapy planning.

Materials

Esophageal cancer patients with pretreatment endoscopy and FDG PET/CT detectable esophageal tumors were recruited retrospectively. The distances from the incisors to the proximal esophageal tumor margins were determined by endoscopy and by the sagittal images of FDG PET/CT. The endoscopic measurement was used as the comparative reference. A nuclear medicine doctor and a radiation oncologist each performed the FDG PET/CT measurement twice for every patient. We analyzed the differences in these measurements, and assessed agreement and reproducibility of the results by the intraclass correlation coefficient (ICC).

Results

Thirty-four patients, with 35 esophageal tumors, were included. By endoscopy and FDG PET/CT, the mean distances from the incisors to the proximal esophageal tumor margin were 27.3 ± 6.4 cm (range 17.1–40.0 cm) and 26.8 ± 6.3 cm (range 15.7–41.3 cm), respectively. The mean absolute differences between the endoscopic and four FDG PET/CT measurements ranged from 1.129 to 1.289 cm (SD: 0.98–1.19). The measurement agreement between FDG PET/CT and endoscopy by ICC was between 0.962 and 0.971. The intra- and interobserver reproducibilities of the two readers were excellent (intraobserver ICC: 0.985, 0.996; interobserver ICC: 0.976–0.984).

Conclusions

FDG PET/CT was in high agreement with endoscopy in measuring the distance from the incisors to the proximal esophageal tumor margin. For FDG PET/CT and CT undetectable esophageal cancer, incorporation of the endoscopic measurement with PET/CT might be a way for making radiotherapy plan.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02206-z.

Long-term clinical outcomes of lipiodol marking using standard gastroscopy for image-guided radiotherapy of upper gastrointestinal cancers

BACKGROUND

Image-guided radiotherapy (IGRT) has significantly improved the precision in which radiotherapy is delivered in cancer treatment. Typically, IGRT uses bony landmarks and key anatomical structures to locate the tumor. Recent studies have demonstrated the feasibility of peri-tumor fiducials in enabling even more accurate delineation of target and normal tissue. The use of gold coils as fiducials in gastrointestinal tumors has been extensively studied. However, placement requires expertise and specialized endoscopic ultrasound equipment. This article reports the long-term outcomes of using a standard gastroscopy to inject liquid fiducials for the treatment of oesophageal and gastric tumors with IGRT.

AIM

To assess the long-term outcomes of liquid fiducial-guided IGRT in a cohort of oesophageal and gastric cancer patients.

METHODS

A retrospective cohort study of consecutive adults with Oesophagogastric cancers referred for liquid fiducial placement before definitive/neo-adjuvant or palliative IGRT between 2013 and 2021 at a tertiary hospital in Melbourne, Australia was conducted. Up to four liquid fiducials were inserted per patient, each injection consisting of 0.2-0.5mL of a 1:1 mixture of iodized oil (Lipiodol; Aspen Pharmacare) and n-butyl 2-cyanoacrylate (Histoacryl^®; B. Braun). A 23-gauge injector (Cook Medical) was used for the injection. All procedures were performed by or under the supervision of a gastroenterologist. Liquid fiducial-based IGRT (LF-IGRT) consisted of computer-assisted direct matching of the fiducial region on cone-beam computerised tomography at the time of radiotherapy. Patients received standard-IGRT (S-IGRT) if fiducial visibility was insufficient, consisting of bone match as a surrogate for tumor position. Radiotherapy was delivered to 54Gy in 30 fractions for curative patients and up to 45Gy in 15 fractions for palliative treatments.

RESULTS

52 patients were referred for liquid fiducial placement within the study period. A total of 51 patients underwent liquid fiducial implantation. Of these a total of 31 patients received radiotherapy. Among these, the median age was 77.4 years with a range between 57.5 and 88.8, and 64.5% were male. Twenty-seven out of the 31 patients were able to have LF-IGRT while four had S-IGRT. There were no complications after endoscopic implantation of liquid fiducials in our cohort. The cohort overall survival (OS) post-radiotherapy was 19 mo (range 0 to 87 mo). Whilst the progression-free survival (PFS) post-radiotherapy was 13 mo (range 0 to 74 mo). For those treated with curative intent, the median OS was 22.0 mo (range 0 to 87 mo) with a PFS median of 14.0 mo (range 0 to 74 mo). Grade 3 complication rate post-radiotherapy was 29%.

CONCLUSION

LF-IGRT is feasible in 87.1% of patients undergoing liquid fiducial placement through standard gastroscopy injection technique. Our cohort has an overall survival of 19 mo and PFS of 13 mo. Further studies are warranted to determine the long-term outcomes of liquid-fiducial based IGRT.

Contribution of FDG-PET/CT to the management of esophageal cancer patients at multidisciplinary tumor board conferences

Background

A multidisciplinary team approach to the management of esophageal cancer patients leads to better clinical decisions.

Purpose

The contribution of CT, endoscopic and laparoscopic ultrasound to clinical staging and treatment selection by multidisciplinary tumor boards (MTB) in patients with esophageal cancer is well documented. However, there is a paucity of data addressing the role that FDG-PET/CT (PET/CT) plays to inform the clinical decision-making process at MTB conferences. The aim of this study was to assess the impact and contribution of PET/CT to clinical management decisions and to the plan of care for esophageal cancer patients at the MTB conferences held at our institution.

Materials and methods

This IRB approved study included all the cases discussed in the esophageal MTB meetings over a year period. The information contributed by PET/CT to MTB decision making was grouped into four categories. Category I, no additional information provided for clinical management; category II, equivocal and misguiding information; category III, complementary information to other imaging modalities, and category IV, information that directly changed clinical management. The overall impact on management was assessed retrospectively from prospectively discussed clinical histories, imaging, histopathology, and the official minutes of the MTB conferences.

Results

79 patients (61 males and 18 females; median age, 61 years, range, 33–86) with esophageal cancer (53 adenocarcinomas and 26 squamous cell carcinomas) were included. The contribution of PET/CT-derived information was as follows: category I in 50 patients (63%); category II in 3 patients (4%); category III in 8 patients (10%), and category IV information in 18 patients (23%). Forty-five patients (57%) had systemic disease, and in 5 (11%) of these, metastatic disease was only detected by PET/CT. In addition, PET/CT detected previously unknown recurrence in 4 (9%) of 43 patients. In summary, PET/CT provided clinically useful information to guide management in 26 of 79 esophageal cancer patients (33%) discussed at the MTB.

Conclusion

The study showed that PET/CT provided additional information and changed clinical management in 1 out of 3 (33%) esophageal cancer cases discussed at MTB conferences. These results support the inclusion whenever available, of FDG-PET/CT imaging information to augment and improve the patient management decision process in MTB conferences.

The treatments and postoperative complications of esophageal cancer: a review

Abstract

Esophageal cancer is still one of the most common cancers in the world. We review the appropriate treatments at different stages of esophageal cancer and also analyze the advantages and disadvantages of these treatments. The prognosis and recovery of different treatment regimens are further discussed. In particular, post-operative complications are the major causes of high mortality derived from the esophageal cancer. Therefore, we particularly discuss the main complications resulting in high mortality after surgery of esophageal cancer, and summarize their risk factors and treatment options.

Background

As the common cancer, the complications of esophageal cancer after surgery have been not obtained systematic treatment strategy, focusing on treatment regimens based on the different stages of esophageal cancers.

Methods and overview

This paper systematically summarizes the appropriate treatment strategies for different stages of esophageal cancers, and their advantages and disadvantages. We particularly focus on the postoperative survival rate of patients and postoperative complications, and discuss the causes of high mortality risk factors after surgery. The risk factors of death and corresponding treatment methods are further summarized in this study.

Conclusion

Postoperative complications is the main cause responsible for the hard cure of esophageal cancers. The existing literatures indicate that postoperative anastomotic fistula is one of the most important complications leading to death, while it has not received much attention yet. We suggest that anastomotic fistula should be detected and dealt with early by summarizing these literatures. It is, therefore, necessary to develop a set of methods to predict or check anastomotic fistula in advance.

Evaluation of metastatic lymph nodes in cN0 thoracic esophageal cancer patients with inconsistent pathological lymph node diagnosis

BACKGROUND

Preoperative clinical diagnosis of lymph node (LN) metastasis and subsequent pathological diagnosis are often not in agreement. Detection of false-negative LNs is essential in selecting an optimal treatment strategy, and most importantly, the presence of false-negative LN is itself a significant prognostic indicator. Therefore, at present, there is an urgent need to establish more accurate and individualized evaluation methods for LN metastasis.

METHODS

Of 213 cN0 patients who underwent curative esophagectomy without preoperative neoadjuvant treatment, 60 (28%) had LN metastasis diagnosed pathologically. There were 129 false-negative LNs, of which 85 were detectable by preoperative computed tomography (CT). We retrospectively investigated the distribution, frequency, and characteristics of pathologically positive nodes in patients with clinically N0 esophageal cancer.

RESULTS

The paracardial region was the most frequent region of false-negative LNs, accounting for 26% (22 LNs) of the total incidence. False-negative LNs distributed widely from the neck to the abdomen in patients with a primary tumor in the middle thoracic esophagus. In patients with a primary tumor in the lower thoracic esophagus, four false-negative LNs were detected in the superior mediastinum. When the short-axis diameter, shape, and attenuation patterns of the LNs were used as criteria for metastasis diagnosis, they were insufficient for an accurate diagnosis. However, false-negative LNs in the most frequently occurring sites are characterized by smaller short-axis, suggesting that accurate diagnosis cannot be made unless the diagnostic criteria for the short-axis are reduced in addition to shape and attenuation.

CONCLUSIONS

Although restrictive to the most frequent regions of false-negative LNs occur, reducing size criterion and consideration of their shape and attenuation may contribute to improved diagnosis.

Association of the primary tumor's SUVmax with survival after surgery for clinical stage IA esophageal cancer: a single-center retrospective study

BACKGROUND

Compared to other esophageal cancers, clinical stage IA esophageal cancer generally has a good prognosis, although a subgroup of patients has a poor prognosis. Unfortunately, clinical diagnoses of invasion depth or lymph node metastasis are not always accurate, which make it difficult to identify patients with a high risk of postoperative recurrence using the tumor-node-metastasis staging system. Fluorodeoxyglucose-positron emission tomography may help guide the identification of malignant tumors and the evaluation of their malignant grade based on glucose metabolism. We aimed to evaluate the association between pre-operative fluorodeoxyglucose-positron emission tomography findings and the postoperative prognosis of patients with clinical stage IA esophageal cancer.

METHODS

This single-center retrospective study evaluated pre-esophagectomy fluorodeoxyglucose-positron emission tomography findings from 38 patients with clinical stage IA esophageal cancer. Receiver operating characteristic curve analysis was performed to evaluate the prognostic significance of the primary tumor having low and high SUVmax values (cut-off: 3.56).

RESULTS

Overall survival (log-rank p = 0.034) and progression-free survival (log-rank p = 0.008) were significantly different between the groups with low SUVmax values (n = 18) and high SUVmax values (n = 20). Furthermore, the primary tumor's SUVmax value was related to pathological vascular invasion (p = 0.045) and distant metastasis (p = 0.042).

CONCLUSION

The SUVmax of the primary tumor is a predictor of postoperative survival for clinical stage IA esophageal cancer. Thus, using fluorodeoxyglucose-positron emission tomography to evaluate the primary tumor's glucose metabolism may reflect the tumor's grade and potentially compensate for inaccuracies in tumor-node-metastasis staging.

Paraneoplastic Syndrome Presenting with Polymyalgia Rheumatica-like Accumulations on 18F-fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

A 70-year-old woman presented with a fever and pain in both lower extremities and the right shoulder and right upper arm continuously for approximately 3 months. ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG/PET-CT) revealed the accumulation of FDG in the right shoulder, lumbar spinous processes, both ischial tuberosities, and both hips and greater trochanters, indicating polymyalgia rheumatica (PMR). In addition, upper gastrointestinal endoscopy revealed esophageal carcinoma. After endoscopic submucosal dissection was performed, her musculoskeletal symptoms spontaneously improved, and the ¹⁸F-FDG/PET-CT findings decreased. In light of these findings, she was diagnosed with paraneoplastic syndrome. When atypical features of PMR, such as asymmetric symptoms occur, we should search for malignancies.

Present and future roles of FDG-PET/CT imaging in the management of gastrointestinal cancer: an update

Positron emission tomography/computed tomography (PET/CT) integrated with 2-[¹⁸F]fluoro-2-deoxy-D-glucose (FDG) is a useful tool for acquisition of both glucose metabolism and anatomic imaging data, as only a single device and one diagnostic session is required, thus opening a new field in clinical oncologic imaging. FDG-PET/CT has been successfully used for initial staging, restaging, assessment of early treatment response, evaluation of metastatic disease response, and prognostication of intestinal cancer as well as various malignant tumors. We reviewed the current status and role of FDG-PET/CT for management of patients with esophageal cancer, gastric cancer, and colorectal cancer, with focus on both its usefulness and limitations.

18 F-Fluorodeoxyglucose positron emission tomography can be used to determine the indication for endoscopic resection of superficial esophageal cancer

¹⁸F‐Fluorodeoxyglucose positron emission tomography (FDG‐PET) is a useful imaging modality that reflects the tumor activity. However, FDG‐PET is mainly used for advanced cancer, not superficial cancer. In this study, we investigated the relationship between the superficial tumor depth of esophageal cancer and the FDG uptake to determine the indications for endoscopic resection (ER). From 2009 to 2017, 444 patients with esophageal cancer underwent esophagectomy or endoscopic submucosal dissection (ESD), and 195 patients were pathologically diagnosed with superficial cancer. Among them, 146 patients were examined by FDG‐PET before esophagectomy or ESD. In these 146 patients, the relationship between the pathological tumor depth and FDG uptake was analyzed. The mean maximum standardized uptake value in pT1a‐EP/LPM tumors was 1.362 ± 0.890, that in pT1a‐MM/pT1b‐SM1 tumors was 2.453 ± 1.872, and that in pT1b‐SM2/SM3 tumors was 4.265 ± 3.233 (P < .0001). Among 51 pT1a‐EP/LPM tumors, 10 (19.6%) showed positive detection of FDG. For pT1a‐MM/pT1b‐SM1 and pT1b‐SM2/SM3 tumors, the detection rate was 52.9% (18/34) and 82.0% (50/61), respectively. The detection rate of pT1a‐EP/LPM was significantly lower than in the other two groups (P < .0001). Among 10 FDG‐PET‐positive lesions, only 1 had no apparent reason for PET positivity; however, 9 of 10 had a suitable reason for detectability by PET and inadequacy for ER. Negative detection of superficial esophageal squamous cell carcinoma by FDG‐PET is useful to determine the indication for ER when the tumor depth cannot be diagnosed even after performing magnifying endoscopy with narrow band imaging and endoscopic ultrasonography. When FDG uptake is recognized, a therapeutic modality other than ER should be considered.

Comparison of two major staging systems of esophageal cancer-toward more practical common scale for tumor staging

The latest 8th edition of TNM Classification of Malignant Tumours by Union for International Cancer Control (UICC) and 11th edition of Japanese Classification of Esophageal Cancer by Japan Esophageal Society (JES) are the two major classifications widely accepted as tools for clinical staging of esophageal cancer. Both systems consist of three main categories, i.e., T, N, and M, but large difference exists between the two. JES system has more detailed sub-classification of T1 tumors reflecting meticulous work by Japanese investigators on superficial esophageal cancer. N-category shows the largest difference. UICC defines the N-category according to only the number of the metastatic regional lymph nodes. The definition of regional nodes in UICC system is static and uniform, and supraclavicular nodes are definitely excluded. In JES system, regional nodes are subgrouped into five different patterns according to the main tumor location, and the supraclavicular nodes are always regional nodes for thoracic esophageal cancer. Japanese surgeons have described the evidence that regional nodes should be dynamically defined according to tumor location and supraclavicular nodes should be included in regional nodes. Compared to the simplified N-category, the staging matrix of UICC system is somewhat complicated. The clinical stage and pathological stage of UICC system are not identical and difference exists also between squamous cell carcinoma (SCC) and adenocarcinoma. It has another system of pathological prognostic grouping. We can imagine several reasons for the difference occurred between the two systems. One is the difference of major pathology. Another reason is the difference of basic concept of cancer treatment. The relative "dependence" on radical surgery in Japan has required the detailed definition of each lymph node station and the evaluation of "efficacy index" of each station. The strict and detailed definition of lymph node stations has been regarded as an obstacle to those who are not familiar with it. Some simplification can be done but maintaining dynamic definition of regional lymph nodes linked to tumor location. If UICC system can accept this concept, I think the two systems can be unified to realize more practical and useful staging system as an international common language.

Influence of region-of-interest determination on measurement of signal-to-noise ratio in liver on PET images

OBJECTIVE

On ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography (PET), signal-to-noise ratio in the liver (SNR_liver) is used as a metric to assess image quality. However, some regions-of-interest (ROIs) are used when measuring the SNR_liver. The purpose of this study is to examine the different ROIs and volumes of interest (VOIs) to obtain a reproducible SNR_liver.

METHODS

This study included 108 patients who underwent ¹⁸F-FDG-PET/CT scans for the purpose of cancer screening. We examined four different ROIs and VOIs; a 3-cm-diameter and a 4-cm-diameter circular ROI and a 3-cm-diameter and a 4-cm-diameter spherical VOI on the right lobe of the patients' livers. The average of SUV (SUV_mean), standard deviation (SD) of SUV (SUV_SD), SNR_liver and SD of the SNR_liver obtained using ROIs and VOIs were then compared.

RESULTS

Although the SUV_mean was not different among the ROIs and VOIs, the SUV_SD was small with a 3-cm-diameter ROI. The largest SUV_SD was obtained with a 4-cm-diameter spherical VOI. The SNR_liver and the SD of the SNR_liver with a 4-cm-diameter spherical VOI were the smallest, while those with a 3-cm-diameter circular ROI were the largest. These results suggest that a small ROI may be placed on a relatively homogeneous region not representing whole liver unintentionally.

CONCLUSION

The SNR_liver varied according to the shape and size of ROIs or VOIs. A 4-cm-diameter spherical VOI is recommended to obtain stable and reproducible SNR_liver.

Concordance of clinical diagnosis of T classification among physicians for locally advanced unresectable thoracic esophageal cancer

BACKGROUND

We conducted a multicenter phase II trial assessing chemoselection with docetaxel plus 5-fluorouracil and cisplatin induction chemotherapy and subsequent conversion surgery for locally advanced, unresectable esophageal cancer. The aim of this study was to validate the concordance of clinical T diagnosis among physicians in the cases of this trial.

METHODS

Computed tomography scans and esophagoscopic images of 48 patients taken at baseline were centrally reviewed by 6 senior physicians with experience in esophageal oncology. Individual reviewers voted for definitive T4, relative T4, relative T3, or definitive T3. Discordant diagnoses between reviewers were resolved by the majority opinion. The reviewers were blinded to patient clinical outcome data and to the vote of the other reviewers.

RESULTS

Ninety percent of cases were diagnosed as clinical T4 by investigators, while 33.3-75.0% (median 70.8%) of cases were judged to be T4 by 6 reviewers. Discordant diagnosis between investigators and reviewers occurred in 33% (16/48) of all cases (Cohen's kappa coefficient 0.0519), including 12 cases where curative resection was considered possible (48%, n = 25) and 4 cases where curative resection was considered impossible (17%, n = 23). Critical discordance (one reviewer voted for definitive T3 but the other voted for definitive T4, and vice versa) between reviewers occurred in 0-12.5% of cases (median 2.1%).

CONCLUSIONS

There were inter-observer variations in clinical diagnosis of the T category of locally advanced, unresectable esophageal cancer. Accurate clinical diagnosis of T classification is required for determining the optimum treatment for each patient.

Improving CT detection sensitivity for nodal metastases in oesophageal cancer with combination of smaller size and lymph node axial ratio

OBJECTIVES

To investigate the value of CT with inclusion of smaller lymph node (LN) sizes and axial ratio to improve the sensitivity in diagnosis of regional lymph node metastases in oesophageal squamous cell carcinoma (OSCC).

METHODS

The contrast-enhanced multidetector row spiral CT (MDCT) multiplanar reconstruction images of 204 patients with OSCC were retrospectively analysed. The long-axis and short-axis diameters of the regional LNs were measured and axial ratios were calculated (short-axis/long-axis diameters). Nodes were considered round if the axial ratio exceeded the optimal LN axial ratio, which was determined by receiver operating characteristic analysis.

RESULTS

A positive predictive value (PPV) exceeding 50% is needed. This was achieved only with LNs larger than 9 mm in short-axis diameter, but nodes of this size were rare (sensitivity 37.3%, specificity 96.4%, accuracy 85.8%). If those round nodes (axial ratio exceeding 0.66 ) between 7 mm and 9 mm in size were considered metastases as well, it might improve the sensitivity to 67.2% with a PPV of 63.9% (specificity 91.6%, accuracy 87.2%).

CONCLUSION

Combination of a smaller size and axial ratio for LNs in MDCT as criteria improves the detection sensitivity for LN metastases in OSCC.

KEY POINTS

• CT is widely used to assess metastatic lymph nodes. • CT has low sensitivity in detecting metastases using conventional criteria. • Diagnostic sensitivity of CT was improved by using lymph node axial ratio. • New diagnostic criteria provide greater diagnostic confidence with PPVs exceeding 50%. • New diagnostic criteria may help clinicians assess patients with oesophageal cancer.

False-Positive Cases of Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomographic Scans in Metastasis of Esophageal Cancer

Of 129 esophagectomies at our institute from June 2010 to March 2015, we experienced three preoperative positron emission tomography-computed tomographic (PET/CT) false positives. Bone metastasis was originally suspected in 2 cases, but they were later found to be bone metastasis negative after a preoperative bone biopsy and clinical course observation. The other cases suspected of mediastinal lymph node metastasis were diagnosed as inflammatory lymphadenopathy by a pathological examination of the removed lymph nodes. Conducting a PET/CT is useful when diagnosing esophageal cancer metastasis, but we need to be aware of the possibility of false positives. Therapeutic decisions should be made based on appropriate and accurate diagnoses, with pathological diagnosis actively introduced if necessary.

Performance of 18-fluoro-2-deoxyglucose positron emission tomography for esophageal cancer screening

AIM

To evaluate the performance of 18-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) for esophageal cancer (EC) screening.

METHODS

We retrospectively analyzed the data of consecutive asymptomatic individuals who underwent FDG-PET and esophagogastroduodenoscopy (EGD) simultaneously for cancer screening at our institution from February 2004 to March 2013. In total, 14790 FDG-PET and EGD procedures performed for 8468 individuals were included in this study, and the performance of FDG-PET for EC screening was assessed by comparing the results of FDG-PET and EGD, considering the latter as the reference.

RESULTS

Thirty-two EC lesions were detected in 28 individuals (31 squamous cell carcinomas and 1 adenocarcinoma). The median tumor size was 12.5 mm, and the depths of the lesions were as follows: Tis (n = 12), T1a (n = 15), and T1b (n = 5). Among the 14790 FDG-PET procedures, 51 examinations (0.3%) showed positive findings in the esophagus; only 1 was a true-positive finding. The screen sensitivity, specificity, positive predictive value, and negative predictive value of FDG-PET for ECs were 3.6% (95%CI: 0.1-18.3), 99.7% (95%CI: 99.6-99.7), 2.0% (95%CI: 0.0-10.4), and 99.8% (95%CI: 99.7-99.9), respectively. Of the 50 FDG-PET false-positive cases, 31 were observed in the lower esophagus, and gastroesophageal reflux disease was observed in 17 of these 31 cases.

CONCLUSION

This study is the first to clarify the FDG-PET performance for EC screening. Based on the low screen sensitivity, FDG-PET is considered to be difficult to use as a screening modality for ECs.

The clinical utility of FDG PET/CT among solid organ transplant recipients suspected of malignancy or infection

PURPOSE

Solid organ transplant (SOT) recipients are at high risk of developing infections and malignancies. 18F-FDG PET/CT may enable timely detection of these diseases and help to ensure early intervention. We aimed to describe the clinical utility of FDG PET/CT in consecutive, diagnostic unresolved SOT recipients transplanted from January 2004 to May 2015.

METHODS

Recipients with a post-transplant FDG PET/CT performed as part of diagnostic work-up were included. Detailed chart reviews were done to extract relevant clinical information and determine the final diagnosis related to the FDG PET/CT. Based on á priori defined criteria and the final diagnosis, results from each scan were classified as true or false, and diagnostic values determined.

RESULTS

Among the 1,814 recipients in the cohort, 145 had an FDG PET/CT performed; 122 under the indication of diagnostically unresolved symptoms with a suspicion of malignancy or infection. The remaining (N = 23) had an FDG PET/CT to follow-up on a known disease or to stage a known malignancy. The 122 recipients underwent a total of 133 FDG PET/CT scans performed for a suspected malignancy (66 %) or an infection (34 %). Sensitivity, specificity, and positive and negative predictive values of the FDG PET/CT in diagnosing these conditions were 97, 84, 87, and 96 %, respectively.

CONCLUSION

FDG PET/CT is an accurate diagnostic tool for the work-up of diagnostic unresolved SOT recipients suspected of malignancy or infection. The high sensitivity and NPV underlines the potential usefulness of PET/CT for excluding malignancy or focal infections in this often complex clinical situation.

Staging Early Esophageal Cancer

Staging esophageal cancer provides a standardized measure of the extent of disease that can be used to inform decisions about therapy and guide prognosis. For esophageal cancer, the treatment pathways vary greatly depending on stage of disease, and accurate staging is therefore crucial in ensuring the optimal therapy for each patient. For early esophageal cancer (T1 lesions), endoscopic resection can be curative and simultaneously gives accurate staging of depth of invasion. For tumors invading the submucosa or more advanced disease, comprehensive investigation is required to accurately stage the tumor and assess suitability for curative resection. A combined imaging approach of computed tomography (CT), positron emission tomography (PET), and endoscopic ultrasound (EUS) offers complementary diagnostic information and gives the greatest chance of accurate staging. Staging laparoscopy can identify peritoneal disease and small superficial liver lesions that could be missed on CT or PET, and alters management in up to 20 % of patients. Optical diagnostic techniques offer the prospect of further extending the possibilities of endoscopic staging in real time. Optical coherence tomography can image superficial lesions and could provide information on depth of invasion for these lesions. Real-time lymph node analysis using optical diagnostics such as Raman spectroscopy could be used to support immediate endoscopic therapy without waiting for results of cytology or further investigations.

FDG PET using SUVmax for preoperative T-staging of esophageal squamous cell carcinoma with and without neoadjuvant chemoradiotherapy

BACKGROUND

Accurate T-staging is pivotal for predicting prognosis and selecting appropriate therapies for esophageal squamous cell carcinoma (ESCC). The diagnostic performance of fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for its T-staging is uncertain. We investigated use of FDG PET/CT for preoperative T-staging of patients with ESCC.

METHODS

Patients with ESCC given preoperative FDG PET/CT scans, either with (CRT[+] group) or without (CRT[-] group) neoadjuvant chemoradiotherapy, were retrospectively reviewed. Maximal standardized uptake value (SUVmax) of the primary tumors on FDG PET/CT scans were measured, and histopathological results were used as the reference standard. The associations between pathological T-stage and potential factors of age, tumor location, tumor grade, tumor size, and tumor SUVmax were analyzed. The cut-off levels of SUVmax for predicting different T-stages and for residual viable tumors after neoadjuvant chemoradiotherapy were determined using receiver operating characteristic analyses.

RESULTS

We enrolled 103 patients (45 in the CRT[-] group; 58 in the CRT[+] group). SUVmax, an independent predictive factor, positively correlated with the pathological T-stage in both groups (CRT[-] group: ρ = 0.736, p < 0.001; and CRT[+] group: ρ = 0.792, p < 0.001). The overall accuracy of the PET/CT with thresholded SUVmax for predicting the pathological T-stage was 73.3% in the CRT[-] group (SUVmax of T0: 0-1.9, T1: 2.0-4.4, T2: 4.5-6.5, T3: 6.6-13.0, T4: >13.0) and 67.2% in the CRT[+] group (SUVmax of T0: 0-3.4, T1: 3.5-3.9, T2: 4.0-5.5, T3: 5.6-6.2, T4: > 6.2). For CRT[-] group, the accuracy using an SUVmax cut-off of 4.4 to differentiate early (T0-1) from locally advanced disease (T2-4) was 82.2% (95% CI, 71.1-93.4%). For CRT[+] group, the accuracy using an SUVmax cut-off of 3.4 to predict residual viable tumors (non-T0) after completion of chemoradiotherapy was 82.8% (95% CI, 73.0-92.5%).

CONCLUSIONS

The FDG avidity of a primary esophageal tumor significantly positively correlated with the pathological T-stage. PET/CT with thresholded SUVmax was useful for predicting T-stage and differentiating residual viable tumors.

Distribution of FDG-avid nodes in esophageal cancer: implications for radiotherapy target delineation

PURPOSE

Clinical target volumes (CTV) for radiotherapy (RT) in esophageal cancer (EC) are based on standard expansions of primary tumor volume. Data is needed to define regions at highest risk for occult disease, based on histology and location of the primary tumor. We therefore reviewed PET scans in EC patients to characterize the location of FDG-avid lymph node metastases (LNM).

MATERIALS AND METHODS

We identified 473 EC patients with reviewable pre-treatment PET-CT scans. Tumors were classified by histology and location; 85% were distal or GE junction tumors and 71% were adenocarcinoma. FDG-avid LNM were classified using standard radiographic nodal atlases, and distances from primary tumor to paraesophageal LNM were also measured.

RESULTS

The most common LNM in upper EC were supraclavicular, retrotracheal and paratracheal. The most common LNM in lower EC were paraesophageal and in the gastrohepatic space. Overall, 55% of paraesophageal LNM were adjacent to primary tumor. Of upper esophageal tumors with paraesophageal LNM, 87% were adjacent to the tumor and none were >6 cm from tumor. However, 57% of lower esophageal tumors with paraesophageal LNM had non-adjacent paraesophageal nodes, 24% of which were >8 cm from the tumor.

CONCLUSION

A more data-driven and individualized approach to CTV delineation could improve the therapeutic ratio of RT in esophageal cancer. These results can guide CTV delineation by indicating the potential distribution of nodal involvement in esophageal cancer.

Impact of PET/CT on radiation treatment in patients with esophageal cancer: A systematic review

PURPOSE

With the advances in radiotracers, positron emission tomography/computed tomography (PET/CT) is recognized as a useful adjunct to anatomic imaging with CT, MRI and endoscopic ultrasonography (EUS). The objective of this review was to comprehensively analyze the roles of PET/CT for the radiotherapy of esophageal cancer.

METHODS

In this review, we focused on issues concerning the application of PET/CT in TNM staging, target volume delineation and response to therapy, both for the primary tumor and regional lymph nodes. Furthermore, the following questions were addressed: how does PET/CT guide appropriate treatment protocols, how does it allow accurate tumor delineation and how does it guide prognosis and future treatment decisions.

RESULTS AND CONCLUSION

For the staging of esophageal cancer, PET/CT played a crucial role in exploring distant malignant lymph nodes and metastasis with high sensitivity, specificity and accuracy. PET/CT using different radiotracer provided a serial of thresholding methods based on standardized uptake value (SUV) to assist in auto-contouring the gross tumor volume (GTV). The change in SUV may offer a potential paradigm of personalized treatment to definitive chemoradiotherapy (CRT). In total, PET/CT has sought to further optimize radiotherapy treatment planning for patients with esophageal cancer.

Comparison of characteristics of 18F-fluorodeoxyglucose and 18F-fluorothymidine PET during staging of esophageal squamous cell carcinoma

OBJECTIVES

The aim of this study was to compare the characteristics derived from fluorine-18 fluorodeoxyglucose (F-FDG) and fluorine-18 fluorothymidine (F-FLT) PET quantitatively and to assess their capacities during staging of esophageal squamous cell carcinoma (ESCC).

MATERIALS AND METHODS

Thirty-six patients with a diagnosis of ESCC who underwent both F-FDG and F-FLT PET were included in this study. Different image-derived indices including the standardized uptake value (SUV), gross tumor length, and texture features were determined. Considering histopathologic examination as the gold standard, the performance of the extracted indices during staging of ESCC was assessed using the Kruskal-Wallis test and the Mann-Whitney test.

RESULTS

Considering the F-FDG PET images, the SUVmax, SUVmean, length (LEN), and eccentricity (EC) were significant during staging of American Joint Committee on Cancer (AJCC) and TNM (P<0.01), whereas for the F-FLT image, the SUVmax, LEN, and EC were significant during staging of AJCC and TNM (P<0.01). The characteristics of F-FDG and F-FLT PET for the classification of ESCC stage were significantly different.

CONCLUSION

F-FDG image-derived characteristics including image textural features, SUV, and shape feature allow for better stratification of AJCC and TNM than F-FLT PET in ESCC patients.

Stage-directed individualized therapy in esophageal cancer

Esophageal cancer is the eighth most common cancer worldwide, and the incidence of esophageal carcinoma is rapidly increasing. With the advent of new staging and treatment techniques, esophageal cancer can now be managed through various strategies. A good understanding of the advances and limitations of new staging techniques and how these can guide in individualizing treatment is important to improve outcomes for esophageal cancer patients. This paper outlines the recent progress in staging and treatment of esophageal cancer, with particularly attention to endoscopic techniques for early-stage esophageal cancer, multimodality treatment for locally advanced esophageal cancer, assessment of response to neoadjuvant treatment, and the role of cervical lymph node dissection. Furthermore, advances in robot-assisted surgical techniques and postoperative recovery protocols that may further improve outcomes after esophagectomy are discussed.

Positron emission tomography for initial staging of esophageal cancer among medicare beneficiaries

BACKGROUND

The role of positron emission tomography (PET) in the initial staging of esophageal cancer is to detect occult metastases, but its ability to do so has not been evaluated at the population-level. In 2001, Medicare approved reimbursement of PET for esophageal cancer staging. We hypothesized rapid adoption of PET after 2001 and a coincident increase in the prevalence of stage IV disease.

METHODS

A retrospective cohort study [1997-2009] was conducted of 12,870 Medicare beneficiaries with esophageal cancer using the Surveillance, Epidemiology, and End-Results (SEER)-Medicare database.

RESULTS

PET use increased from <3% before 2001 to 44% in 2009 (post-PET era) (P trend <0.001). Over the same period, the prevalence of stage IV disease also increased (20% in 1997 and 28% in 2009, P trend <0.001). After adjusting for changing patient characteristics over time, the rate of increase in stage IV disease in the post-PET era [relative risk (RR) =1.06; 95% confidence interval (CI), 1.00-1.13] was no different than the rate of increase in the pre-PET era (RR =1.02; 95% CI, 1.02-1.04). Over the entire study period, the prevalence of unrecorded stage decreased by more than half (43% to 18%, adjusted P trend <0.001) with coincident increases in stage 0-III (37% to 53%, adjusted P trend <0.001) as well as stage IV disease.

CONCLUSIONS

The increasing frequency of PET use and stage IV disease over time is more likely explained by improved documentation rather than PET's ability to detect occult metastases. The absence of compelling population-level impact compliments previous studies, revealing an opportunity to increase value through selective use of PET.

The 100 most cited articles investigating the radiological staging of oesophageal and junctional cancer: a bibliometric analysis

Objectives

Accurate staging of oesophageal cancer (OC) is vital. Bibliometric analysis highlights key topics and publications that have shaped understanding of a subject. The 100 most cited articles investigating radiological staging of OC are identified.

Methods

The Thomas Reuters Web of Science database with search terms including “CT, PET, EUS, oesophageal and gastro-oesophageal junction cancer” was used to identify all English language, full-script articles. The 100 most cited articles were further analysed by topic, journal, author, year and institution.

Results

A total of 5,500 eligible papers were returned. The most cited paper was Flamen et al. (n = 306), investigating the utility of positron emission tomography (PET) for the staging of patients with potentially operable OC. The most common research topic was accuracy of staging investigations (n = 63). The article with the highest citation rate (38.00), defined as the number of citations divided by the number of complete years published, was Tixier et al. investigating PET texture analysis to predict treatment response to neo-adjuvant chemo-radiotherapy, cited 114 times since publication in 2011.

Conclusion

This bibliometric analysis has identified key publications regarded as important in radiological OC staging. Articles with the highest citation rates all investigated PET imaging, suggesting this modality could be the focus of future research.

Main Messages

• This study identifies key articles that investigate radiological staging of oesophageal cancer.

• The most common topic was accuracy of staging investigations.

• The article with the highest citation rate investigated the use of texture analysis in PET images.

Potential impact of (18)FDG-PET/CT on surgical approach for operable squamous cell cancer of middle-to-lower esophagus

Background

Fluorodeoxyglucose-positron emission tomography (PET)/computed tomography (CT) is reported to have a significant advantage over CT for staging esophageal cancer (EC). However, whether PET/CT may play a useful role in guiding surgical approach remains undetermined.

Methods

Patients with potentially resectable squamous cell EC were randomized into either PET/CT group or CT group. The surgical data and survival outcomes were compared.

Results

Compared to the CT group, the right-sided approach was more frequently used (42.6% versus 25.5%, P=0.065) in the PET/CT group in order to allow surgical access to radiographically suspicious lymph nodes inaccessible from the left, thus enabling the removal of more involved lymph nodes (2.83 versus 1.76; P=0.039) as well as their stations (1.65 versus 1.08; P=0.042). Although the overall survival between the two groups was similar, the PET/CT group had a longer disease-free survival (DFS) than the CT group (27.1 months versus 18.9 months; P=0.019), especially in the subgroup of node-positive patients (22.5 months versus 13.5 months; P=0.02). Preoperative imaging arm was the only prognostic factor found to independently influence DFS.

Conclusion

For patients with middle-to-lower EC, surgical approaches directed by PET/CT may increase the likelihood of complete resection and affect DFS.

[Usefulness of Determining Acquisition Time by True Count Rate Measurement Method for Delivery 18F-FDG PET/CT]

A stable quality of delivery 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) requires suitable acquisition time, which can be obtained from an accurate true count of 18F-FDG. However, the true count is influenced by body mass index (BMI) and attenuation of 18F-FDG. In order to remove these influences, we have developed a new method (actual measurement method) to measure the actual true count rate based on sub-pubic thigh, which allows us to calculate a suitable acquisition time. In this study, we aimed to verify the acquisition count through our new method in terms of two categories: (1) the accuracy of acquisition count and (2) evaluation of clinical images using physical index. Our actual measurement method was designed to obtain suitable acquisition time through the following procedure. A true count rate of sub-pubic thigh was measured through detector of PET, and used as a standard true count rate. Finally, the obtained standard count rate was processed to acquisition time. This method was retrospectively applied to 150 patients, receiving 18F-FDG administration from 109.7 to 336.8 MBq, and whose body weight ranged from 37 to 95.4 kg. The accuracy of true count was evaluated by comparing relationships of true count, relative to BMI or to administered dose of 18F-FDG. The PET/CT images obtained by our actual measurement method were assessed using physical index. Our new method resulted in accurate true count, which was not influenced by either BMI or administered dose of 18F-FDG, as well as satisfied PET/CT images with recommended criteria of physical index in all patients.

Predictive value of repeated F-18 FDG PET/CT parameters changes during preoperative chemoradiotherapy to predict pathologic response and overall survival in locally advanced esophageal adenocarcinoma patients

INTRODUCTION

The goal of the current study was to investigate the predictive and prognostic values of repeated F-18 FDG PET/CT parameter changes for prediction of complete pathologic response (pCR) in patients with adenocarcinoma of locally advanced esophageal cancer (LAEC) who received preoperative concurrent chemoradiotherapy (PCRT).

METHODS

A total 53 patients with LAEC patients were included in the current study. All patients were evaluated by F-18 FDG PET/CT before and during chemoradiotherapy. The percent changes (∆, %) in F-18 FDG PET/CT parameters were used to predict pCR and to calculate overall survival (OS). The predictive value for pCR of F-18 FDG PET/CT cutoff values was determined by ROC analysis. The prognostic significance was assessed using Kaplan-Meier analysis.

RESULTS

pCR occurred in 15 patients (28.3 %). When ΔSUVmax > 23.5 % was used as cutoff, the sensitivity and specificity of F-18 FDG PET/CT for prediction of pCR were 100 % and 52.6, respectively. The AUC was 0.750 (95 % CI; 0.612-0.859), and standard error (SE) was 0.0633 (p = 0.0002). ΔMTV resulted in 80 % sensitivity, 76.3 % specificity, and 0.731 AUC (95 % CI; 0.591-0.843, SE = 0.077, p = 0.0027) for cutoff values >25.5 %. When ΔTLG > 44.8 % was used as cutoff, the sensitivity and specificity of F-18 FDG PET/CT for prediction of pCR were 100 and 65.8 %, respectively. The AUC was 0.893 (95 % CI; 0.777-0.961), and SE was 0.0431 (p < 0.0001). Kaplan-Meier analysis showed that high ΔSUVmax, ΔMTV, and ΔTLG were associated with improved OS.

CONCLUSION

In conclusion, the current study shows the capability of the changes (Δ) in repeated F-18 FDG PET/CT parameters to predict the achievement of pCR during PCRT in LAEC patients. Among the parameters, the ΔSUVmax, ΔMTV, and ΔTLG were predictors for pCR and well associated with OS.

Esophageal Cancer: Role of Imaging in Primary Staging and Response Assessment Post Neoadjuvant Therapy

Advances in the early detection and treatment of esophageal cancer have meant improved survival rates for patients with esophageal cancer. Accurate pretreatment and post-neoadjuvant treatment staging of esophageal cancer is essential for assessing operability and determining the optimum treatment plan. This article reviews the multimodality imaging approach in the diagnosis, staging, and assessment of treatment response in esophageal cancer.

Determination of regional lymph node status using (18)F-FDG PET/CT parameters in oesophageal cancer patients: comparison of SUV, volumetric parameters and intratumoral heterogeneity

OBJECTIVE

We aimed to investigate whether the standardized uptake values, volumetric parameters and intratumoral heterogeneity of fluorine-18-fludeoxyglucose ((18)F-FDG) uptake could predict regional lymph node (rLN) metastasis in oesophageal cancer.

METHODS

51 patients with surgically resected oesophageal cancer were included in the present study. The (18)F-FDG positron emission tomography (PET)/CT findings and rLN metastasis were compared with the histopathological results. The intratumoral metabolic heterogeneity was represented by the heterogeneity factor (HF), which was determined for each patient. Univariate and multivariate analyses were used to analyse the associations between the rLN metastasis and clinical findings, standardized uptake values, metabolic tumour volume (MTV), total lesion glycolysis (TLG) and HF.

RESULTS

The rLN(+) group showed statistically significant higher values of MTV (median, 13.59 vs 6.6; p = 0.0085), TLG (median, 119.18 vs 35.96; p = 0.0072) and HF (median, 3.07 vs 2.384; p = 0.0002) than the rLN(-) group. Univariate analysis showed that maximum standardized uptake value, mean standardized uptake value, MTV, TLG and HF were significantly associated with pathologic rLN involvement. However, in multivariate analysis, the HF was a potent associated factor for the prediction of pathologic rLN metastasis in oesophageal cancer.

CONCLUSION

In conclusion, (18)F-FDG PET/CT parameters such as maximum standardized uptake value, mean standardized uptake value, MTV, TLG and HF were useful for the prediction of pathologic rLN status in patients with oesophageal cancer. However, HF might be the most powerful predictor of rLN metastasis of patients with oesophageal cancer.

ADVANCES IN KNOWLEDGE

Assessment of intratumoral heterogeneity of (18)F-FDG PET/CT may be a useful adjunct for rLN staging of oesophageal cancer.

[Are extensive fields useful for radiotherapy of esophageal cancer?]

PURPOSE

Study of the pattern of relapse for locally advanced oesophageal cancer and analysis of the local recurrences according to irradiated volume.

PATIENTS AND METHODS

We performed a monocentric retrospective study of patients treated in the integrated centre of oncology (Angers, France). Two treatment strategies were used: concurrent chemoradiation alone or followed by surgery. Recurrences were classified as: locoregional, either isolated or associated with distant metastasis, and metastatic only. Locoregional relapses were subclassified as in-field, out-field, or mixed.

RESULTS

Between March 2004 and October 2011, 168 patients were treated: 130 by chemoradiation, and 38 by chemoradiation followed by surgery. The median supero-inferior margins added to the gross tumour volume in order to create the planning tumour volume was 5cm (range: 0.5-21). Sixty-two percent of patients (n=104) relapsed: 82 locoregional relapses (49%), including 45 isolated relapses (27%) and 37 associated with distant metastasis relapses (22%), and 22 metastatic relapses (13%). From the 82 locoregional relapses, only four isolated relapses were exclusively out-field.

CONCLUSION

With 5cm supero-inferior margins added to gross tumour volume, less than 3% of patients had an isolated out-field recurrence. However, half of the patients suffered in-field local recurrence and one third had metastases. These findings advocate for a limited prophylactic nodal irradiation. Trials are ongoing to assess dose escalation or surgery in order to increase local control.

Role of fluorine 18 fluorodeoxyglucose positron emission tomography/computed tomography in gastrointestinal cancers

Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has become a routine imaging modality for many malignancies and its use is currently increasing. In the present review article, we will summarize the evidence for FDG-PET/CT use in digestive cancers (excluding neuroendocrine tumours), and review the existing recommendations. While PET/CT is nowadays considered to be an important tool in the initial workup of oesophageal and anal cancers, new data are emerging regarding its use in assessing therapeutic efficacy, radiotherapy treatment planning, and detection of recurrence in case of isolated tumour marker elevation. Moreover, PET/CT may help decision making by detecting distant metastatic sites especially in potentially resectable metastatic colorectal cancer and, to a lesser extent, in localized gastric and pancreatic cancers. Finally, incidental focal colonic FDG uptakes require exploration by colonoscopy, as they are often associated with premalignant or malignant lesions.

Appropriateness criteria of FDG PET/CT in oncology

(18)Fluorine-2-fluoro-2-Deoxy-d-glucose ((18)F-FDG) positron emission tomography/computerized tomography (PET/CT) is a well-established functional imaging method widely used in oncology. In this article, we have incorporated the various indications for (18)FDG PET/CT in oncology based on available evidence and current guidelines. Growing body of evidence for use of (18)FDG PET/CT in select tumors is also discussed. This article attempts to give the reader an overview of the appropriateness of using (18)F-FDG PET/CT in various malignancies.

Preoperative evaluation of oesophageal adenocarcinoma

The preoperative evaluation of oesophageal adenocarcinoma involves endoscopic ultrasound (EUS), computed tomography (CT), and positron emission tomography (PET). With routine Barrett's oesophagus surveillance, superficial cancers are often identified. EUS, CT and PET have a limited role in the staging of superficial tumours. Standard EUS has limited accuracy, but high frequency ultrasound miniprobes are valuable for assessing tumour stage in superficial tumours. However, the best method for determining depth of invasion, and thereby stage of disease, is endoscopic mucosal resection. In contrast, in advanced oesophageal cancers, a multi-modality approach is crucial. Accurate tumour staging is very important since the treatment of advanced cancers involves a combination of chemotherapy, radiation, and surgery. EUS is very useful for staging of the tumour and nodes. High frequency ultrasound miniprobes provide the ability to perform staging when the lesion is obstructing the oesophageal lumen. CT and PET provide valuable information regarding node and metastasis staging.

Reliability of (18)f-fluorodeoxyglucose positron emission tomography/computed tomography in the nodal staging of colorectal cancer patients

Purpose

Lymph-node metastasis is considered as critical prognostic factor in colorectal cancer. A preoperative evaluation of lymph-node metastasis can also help to determine the range of distant lymph node dissection. However, the reliability of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the detection of lymph-node metastasis is not fully known.

Methods

The medical records of 433 patients diagnosed with colorectal cancer were reviewed retrospectively. FDG-PET/CT and CT were performed on all patients. Lymph nodes were classified into regional and distant lymph nodes according to the American Joint Committee on Cancer (AJCC) Cancer Staging Manual, 7th edition.

Results

The patients included 231 males (53.3%) and 202 females (46.7%), with a mean age of 64.7 ± 19.0 years. For regional lymph nodes, the sensitivity of FDG-PET/CT was lower than that of CT (57.1% vs. 73.5%, P < 0.001). For distant lymph nodes, the sensitivity of FDG-PET/CT was higher than that of CT (64.7% vs. 52.9%, P = 0.012). The sensitivity of FDG-PET/CT for regional lymph nodes was higher in patients with larger primary tumors. The positivity of lymph-node metastasis for FDG-PET/CT was affected by carcinoembryonic antigen levels, tumor location, and cancer stage for regional lymph nodes and by age and cancer stage for distant lymph nodes (P < 0.05).

Conclusion

The sensitivity of FDG-PET/CT for regional lymph-node metastasis was not superior to that of CT. However, FDG-PET/CT provides helpful information for determining surgical plan especially in high risk patients group.